Abstract: An improved slide for electrophotographic film which comprises a pair of slide frame forming panels hingedly connected along adjacent edges enabling the panels to be folded together in superposed relation. The inner surfaces of each panel is coated with a pressure sensitive adhesive which bonds an electrophotographic film to one panel. A transparent protective film or a second photographic film may be bonded to the other panel. A conductive foil strip is affixed along an edge of the film for providing a grounding contact required for imaging the film in a duplicating camera and a release paper is disposed over the adhesive coating of the other panel. Subsequent to imaging, a slide is formed by stripping off the release paper and folding the panels so that the adhesive coating bonds the inner surfaces together with the film being retained therebetween.

Abstract: A slide viewer/sorter having a chute oriented at an incline to horizontal which is adapted to receive a photographic slide at one end. The slide drops by force of gravity to a viewing station where it is held by a detent. After viewing the slide the detent is actuated to release the slide which is transported by force of gravity to the lower end of the chute where it drops into a first receptacle. The first receptacle is rotatably mounted so that it can be moved out of the way, thus allowing the slide to drop further down into a second receptacle, having a number of bins. The second receptacle is mounted so that any bin can be positioned under the chute. This allows the operator of the viewer/sorter to sort the slides into two or more different stacks.

Abstract: A pendant type capsule is provided to be worn on the person as jewelry and having within an air and water-tight cavity therewithin a small microfilm containing the medical history or medical and personal characteristics of the person carrying or wearing the jewerly together with a suitable light sensitive backing for or adjacent to the film to provide lighting characteristics, and a lens at the other end of the cavity, with the film and lens fixedly mounted to provide fixed focus for observing the medical history of the person without the necessity of using other devices.

Abstract: An attractive dynamic star burst display is provided in which a plurality of light sources preferably of different colors, are mounted behind a translucent enclosure, and relative movement is provided for effectively changing the distances between the light sources and the regions of the surface where their various rays are being viewed. The translucent enclosure includes a layer of intrinsically transparent material having a smooth inner surface facing the light sources and an embossed outer surface having a multifaceted pyramidal prism system for directing rays of light from the light sources in dynamically changing light patterns in accordance with the optical and geometric relationship involved, including the position of the viewer's eyes, the multi-facets on the embossed outer surface and the effective distance between the respective light sources and the respective regions on the embossed outer surface where the rays of light are being seen.

Abstract: Sight devices of many guns are not wholly satisfactory. When guns such as 5 caliber automatic pistols are to be used in competitive target shooting, more expensive gun sights are utilized. Simpler gun sights are available but they present visual problems. A rear gun sight apparatus is provided herein which improves visual sighting or aiming, and it can be readily manufactured at a low cost and by simple manufacturing methods.

Abstract: An infant development toy comprising a plurality of rings of varying diameter connected to each other and to a central object by a flexible connecting means. Optionally, the connecting means may be extended outside the rings to form a primary handle, and a bell may be contained within the central object or the primary handle. The rings and central object are of a size, and are spaced along the connecting means in such a manner that, when the toy is held aloft by and suspended from the point of connection of the largest ring and the connecting means, the rings are concentric and surround the central object.

Abstract: A toy hovercraft apparatus and which includes a toy hovercraft and a launcher therefor. The hovercraft comprises a frame having an outwardly flaring skirt with a downwardly projecting peripheral lip to form an air chamber therebeneath. A motor, e.g., an electric motor, supported centrally of the skirt, rotates a fan located in an upper portion of the chamber to draw in air through inlets and create a pressurized air cushion in the chamber, which, in turn, causes the hovercraft to float or hover over a floor, or other surface. One or more relatively small rechargeable batteries are also carried on the frame and connected to the electric motor for powering the motor and the batteries may be periodically recharged. The hovercraft is preferably round and is constructed so that the weight is symetrically distributed which permits the torque created by the fan to cause rapid rotation of the hovercraft in a level horizontal plane without imparting horizontal motion to the hovercraft.

Abstract: A bubble-blowing device enabling the formation of bubbles considerably larger than has been possible heretofore with less expenditure of energy, and further characterized by absence of moving parts, simplicity of operation, low cost and production of a greater number of bubbles per charge of bubble-blowing solution.

Abstract: A novel construction toy includes at least one substantially planar sheet containing a printed pattern on its surface; a plurality of colored interstacking blocks capable of intercoupling, such as frictionally interlocking, with one another to form a pattern corresponding to the pattern printed on said sheet; an elongate grid block capable of intercoupling with said blocks, and a support structure for holding said grid block and said pattern sheet with the latter in a position underlying said grid block; which support structure includes a first elongated member containing a first planar surface and a second planar surface recessed from said first to define a ledge; means for mounting the grid block in a position on said first member so as to protrude into a position overlying said second recessed surface and thereby define a channel for receiving an edge of the sheet; and a second member coupled to said first member for holding the sheet member from said other end; whereby said intercoupling blocks may be bui

Abstract: The mother doll is provided with fasteners on the tip of each breast and a baby doll is provided with a complimentary fastener at the mouth so that breast feeding is simulated upon joining of the fasteners. The mother doll is also provided with complimentary fasteners on the extremities of the arm to lock the arms about the baby doll to hold the baby doll against the mother doll. The fasteners may be Velcro, snaps or any other suitable device.

Abstract: A doll comprising a crying sound generator within the doll body, first switch means for actuating the crying sound generator, at least two additional switch means, and automatic selection means for determining which of the additional switch means is connected to stop the crying. The additional switch means may be operated by manipulating the doll, e.g., by giving it a bottle, by changing its diaper, or by picking it up and patting its back. In a play sequence the child actuates the switch to produce crying sounds and then attempts to stop the crying by handling the doll in one of the ways stated. When the child hits upon the type of handling which operates the particular additional switch means selected by the random selector, the crying sounds stop. A short sequence of sighing or cooing sounds may be used at the end of the crying sounds.

Abstract: A toy space vehicle having a main body. A door in the upper surface of the main body may be caused to slowyly open and close accompanied by sounds simulating the movement of heavy doors. Pods affixed to the main body may be made to slowly open or close accompanied by the same sounds. A gun residing in the main body may be caused to fire and aircraft residing in the pods to be launched when the doors are opened.

Abstract: A solar energy heated structure, such as an occupied building or greenhouse, includes a walled structure enclosing space volume. A movable insulated panel with a reflective surface is pivotably supported within the space volume. In a first position the panel cooperates with an insulated portion of the walled structure to enclose a lower portion of the space volume containing the occupied portion or plant bed and prevents loss of heat therefrom. In a second position the panel is disposed in an upper portion of the space volume, so that solar energy entering the overall space volume through a light transmitting portion of the walled structure is reflected onto the solar energy user by the reflective surface of the panel.

Abstract: A container for sprouting seeds hydroponically without water build-up causing root rot. The container includes a bottom portion joined to side walls, a bendable seed-holding tray and a conventional cover. The bottom portion has ribs for supporting the tray for limited free angulation to different nonhorizontal positions, and the side walls have channels to allow water run-off.

Abstract: A plant support apparatus including first and second collar portions forms a cylindrical collar. A rectangular flange extending from an end of the cylindrical collar includes holes for connecting guidelines thereto. The flange includes a pair of arcuate slots disposed therein on opposing sides of a plane about which said cylindrical collar is split, with radially outer sides of said slots open to opposing sides of said rectangular flange. The collar portions are held together by flexible lines engaging notches of the arcuate slots.

Abstract: Compositions are disclosed comprising a water insoluble microgel which when used as a coating for seeds provides protection for the seeds and may be used as a carrier for materials such as fertilizers, herbicides, pesticides, etc. The microgel does not dissolve when contacted with water, but the outer layer of the microgel swells and falls away, thereby dissrupting the coating, and continues until the coating is removed. An advantage of such a coating is that there is no dissolved material available to fill the pores of the seeds to thereby retard germination. The coating quickly disintegrates upon contact with water for releasing any carried substances and exposing the seeds to their natural environment.

Abstract: A device for transporting a plant having a root system confined in a ball of earth. The device comprises a flexible strip which is placed around the ball of earth in belt-like fashion, a means for winding the strip so as to tightly grip the ball, and a means for locking the strip in position as the ball is being transported.

Abstract: A window guard assembly has features that allow it to be released from the inside to allow occupants to escape in case of fire. The window guard assembly also has features that prevent the locking mechanism from being actuated by an intruder on the outside of the building. The guard assembly has a guard mounted to a window frame for covering a window. The guard is pivotally mounted, and a locking mechanism selectively prevents the pivoting of the guard. A latch member controls the locking mechanism. An enclosure is formed around the latch member to prevent access from the exterior. The enclosure has an opening that faces the interior. A pair of doors are located at the opening, one with a vertical hinge, and the other with a horizontal hinge. Both of these doors require opening to reach the latch member. When opened, the doors form a barrier in cooperation with the window frame that requires the intruder to attempt to reach around the doors in order to reach the latch member.

Abstract: A mobile rail grinding machine comprises a machine frame mounted on the rails of a track for continuously moving in the direction of, and along, the track, a tool carrier frame vertically adjustably mounted on the machine frame, a rail grinding tool or a group of such tools mounted on the carrier frame for vertical adjustment in a direction vertical to the machine frame to press the tool or tools against surface areas of the rails to grind irregularities off the surface areas, and a drive for imparting to the tool carrier frame a reciprocating working movement in the direction of the track independent of, and additional to, that simultaneously imparted to it by the movement of the machine frame. The invention also is directed to a rail grinding method wherein the rail is ground by such a compound working movement.

Abstract: A diamond paste to be used for treating surfaces of workpieces comprising diamond powder in a mechanical mixture with surface-active and lubricating (cooling) components.

Abstract: An adapter for a honing mandrel for finishing the interior surfaces of bores using a honing mandrel having an abrasive member positioned in an opening therein, a wedge member for radial adjustment of the abrasive member during a honing operation to maintain the abrasive member engaged with the bore being honed, the improvements comprising an adapter having means for receiving and supporting the honing mandrel, the adapter including a wedge engaging member adjustable thereon to engage the wedge member to permit longitudinal movement thereof in the mandrel but to prevent radial movement thereof, the adapter also including a pair of angularly related mandrel engaging and locating surfaces against which the mandrel is positioned during installation on the adapter, a threaded member adjustable in the adapter to maintain the mandrel against said locating surfaces, an elongated member having one end attached to said adapter and on an opposite end, said elongated member being biased under spring tension into engageme

Abstract: A sanding block having a handle portion from which projects an elongate support portion to which can be adhered a strip of pressure-sensitive adhesive-coated finishing material. The support portion has various shaped surface portions for supporting the finishing material, including a planar surface portion, an arcuate surface portion of decreasing radius extending longitudinally of the support portion away from the handle portion, and an edge surface portion provided by planar surface portions intersecting at an acute included angle so that the finishing material may be supported in a desired shape that affords pressing and rubbing it against a complementary surface on a workpiece by manual manipulation of the sanding block.

Abstract: A combination comprising a blade block for mounting on an abrasive throwing wheel and a blade for mounting on the blade block is provided. The blade has a front surface and a rear surface, a first opening on the rear surface and a second opening on the rear surface spaced from the first opening. The blade block is provided with projecting means, such as a lug, adapted for insertion in the first opening on the rear of the blade. An abutment means contacts the rear of the blade. An opening in the blade block is provided, and the opening is intermediate the projecting means and the abutment means on the blade block. The blade is held in position on the blade block by locking means, such as a deformable, resilient wire, adapted for insertion in the second opening on the rear of the blade and for insertion in the opening in the blade block.

Abstract: Self-erecting apparatus for transporting and temporarily storing material such as asphalt; the apparatus includes a surge bin and a drag chute for transporting the asphalt material from a drum plant to the surge bin. The drag chute and the surge bin are pivotally attached to each other and to a flat bed trailer, permitting their simultaneous raising and lowering by means of a winch apparatus attached by means of cables to the support legs of the surge bin to provide ease of lowering the bin for transportation of the apparatus from one site to another and ease in erecting the bin at a new site. A foldable side panel of the surge bin permits the drag chute to nest in the surge bin thus providing a more compact arrangement of the apparatus when in the lowered configuration.

Abstract: A tank adapted to withstand the horizontal displacement forces and overturning moments which act upon the side walls thereof under earthquake conditions is disclosed. The tank includes a base and cylindrical side walls and a plurality of tendons are provided each of which is attached to the cylindrical side wall at one end and to an anchor fixedly positioned in the concrete base. Each of the tendons is stressed and the stress in the tendon acts downwardly and in some embodiments radially outwardly on the tank wall and substantially restrains the wall from horizontal displacement and protects the side walls from the stresses developed due to the overturning moment. Steel-wall and prestressed concrete wall tanks, particularly for cryogenic liquids, can be adapted according to the invention.

Abstract: The fire barrier assembly is comprised of a frame through which one or more electrical cables may be passed and a plurality of sealing elements clamped in the frame in contact with each electrical cable and the frame to provide an airtight barrier. Each element has a plate-like configuration and is comprised of an elastomeric body having intumescent material mixed therewith and opposing end members connected by bolts so that upon movement of the end members toward each other the elastomeric body will expand into intimate engagement with adjacent elements, the frame and each cable passing through the frame. Adjacent elements on opposite sides of an electrical cable are provided with complimentary grooves to define a cylindrical passage for each cable and additional filler elements may be provided without grooves. An external coating of intumescent material is applied to the outer surfaces only of the frame and end members to provide a heat insulating layer.

Abstract: A reinforced insulated wall construction having a core of thermal insulation material which is reinforced by high-slenderness-ratio reinforced concrete columns. High compressive and side-load strengths are achieved by centrally supporting reinforcing members in vertical passageways in the core while the remainder of each passageway is filled with a concrete slurry and by so centrally supporting the members until the slurry hardens into concrete. Further side-load strength enhancement may be achieved by encasing at least a central length portion of each concrete column in a high flexural strength structural tubular casing.

Abstract: A modified dovetail joint interconnects a plywood web to a chord. The chord carries two grooves extending inwardly from the surface of the chord intersected by the web. The two grooves merge into a single, wider groove adjacent the surface of the chord, are separated by a wedge-shaped spacer, and are inclined relative to each other. The plywood web carries two flexible tongues along its edge portion that are sized to engage respective ones of the grooves in the chord. The tongues are composed, at least in part, of two of the veneer layers of the plywood and are spaced from each other by a web groove formed in an intervening layer of veneer. The inner terminus of the web groove as well as the terminus of the glue laminate between the tongue forming layers of veneer and the adjacent intervening layer both lie below the surface of the chord when the web and the chord are assembled.

Abstract: In an automobile windshield structure in which a windshield glass is adhesively attached to a body frame, a clip device for installing a moulding along the peripheral edge portion of the glass comprises first and second lip members. The first clip member is adapted to be attached to the peripheral edge of the glass and has guide channels for slidably receiving cooperating slide portions in the second clip member. The first clip member has a retaining pawl which is adapted to engage with indentations on the second clip member so that the second clip member is prevented from moving in one direction with respect to the first clip member but movable in the opposite direction.

Abstract: A tubular synthetic-resin body usable as a roadway marker comprises spaced upper and lower tubular parts interconnected by thin webs formed integrally with the upper and lower parts. A middle part of contrasting color lies between these upper and lower parts and has grooves receiving the connecting webs. Such a roadway marker is made by fitting the middle part over a core of a mold, and then injecting synthetic-resin material into the mold around this sleeve so as to form the upper and lower parts and the web.

Abstract: Method and apparatus for forming and laying paving blocks in which interchangeable grids are provided of dissimilar configuration comprising a plurality of mould cavities each enclosing one or more fixed centers of the modules of the pattern, whatever is in the conformation of the said grids. The modular and transformable ramming assembly comprises a plurality of fixed securing points distributed to correspond to the fixed centers of the modules of the mould pattern and intended for the removable fitting of ramming plates of forms and dimensions analogous with those of the underlying cavities of the selected grid. The changing of forms and/or dimensions of the moulded paving stones or slabs is effected by replacing one grid by another differently conformed grid and by fixing new removable ramming plates corresponding to the forms and/or dimensions of the cavities of the new grid, by means of the said fixing points.

Abstract: Wire-mesh webs formed from interengaged flattened spirals, especially chain-link fencing, upon manufacture are coiled by twisting the planes of the spirals so that they fit tightly together and almost coincide with axial planes of the roll. During the coiling process, one to three tension elements are introduced into the corresponding troughs of the successive undulations formed by the successive spirals and are maintained under tension during coiling to maintain the spirals in their substantially erect condition. The result is a highly compact roll.

Abstract: The invention relates to transport apparatus for transport containers in the area where blanks are loaded into a transport container of a carton filling machine. A plurality of first free-wheeling transport rollers are provided in the loading area and a plurality of rollers outside the loading area which are driven by a drive belt. The drive belt is raised to pass over a first diverting roller at the beginning of the loading area then returned at the end of the loading area by passing over a second diverting roller. A second free-wheeling transport roller is provided which is movable into and out of engagement with the drive belt.

Abstract: In a method of automatically closing a large upright sack after filling, the top of the flattened filling end of the sack is folded over onto itself and a closure tape is secured to the folded-over portion and one wall of the sack, whereafter the filling end is re-erected substantially vertically, folded in zig-zag fashion and pulled together to form a frill. The ends of the tape project beyond both sides of the filling end so that, after zig-zag folding of the filling end and tape and after the frill has been formed, the tape ends project from the same side of the frill and can be interconnected.

Abstract: A method for applying a threaded closure to a container, said closure having sealing means in or towards the crown thereof, which method comprises applying the closure to the container by the application of a predetermined rotary torque thereto, continuing the application of the closure to the container until the desired torque applied is obtained and thereafter applying axial pressure to the closure crown towards and on to the container while simultaneously applying said torque whereby the closure pressure serves to disengage the threads to overcome at least some of the friction therebetween to permit a greater proportion of the applied torque to be applied to the sealing means within the closure.

Abstract: Herein disclosed is an incorrect coin number detector to be used with a coin wrapping machine for detecting whether or not a preset number of piled coins are correctly wrapped when the both ends of wrapping paper are fastened by means of a pair of fastening claws. The incorrect coin number detector includes stroke setting means for setting the stroke of the one of the fastening claws and accordingly the shortest spacing inbetween. Further inclusive is actuating means for moving the one fastening claw toward the other with the aid of a coil spring. Still further inclusive is incorrectness detecting means having a detecting switch for generating, when actuated by the fastening claw moving mechanism through an actuating lever, the signals which are indicative of the incorrectness in the number of the piled coins being wrapped.

Abstract: A heat-seal type wrapping apparatus which operates by wrapping successive pieces of candy at regular intervals in a plastic film being unwound from a reel and being formed into a cylinder, subjecting the cylinder of plastic film to longitudinal heat seal along its overlapping margins and then to transverse heat seal between adjacent wrapped pieces of candy, and centrally severing the transversely heat-sealed regions. The apparatus comprises a device for preheating the overlapping margins of the film to a suitable temperature prior to the longitudinal heat seal and a device for preheating transverse heat-seal regions to a suitable temperature prior to the transverse heat seal, thereby ensuring satisfactory heat seal both longitudinal and transverse.

Abstract: A support arrangement and discharge structure for individual picking units of a four-row cotton picker. The outboard picking units are transversely cantilevered from the inboard units using telescoping cross members which are adjustable to properly position the units for various row spacings. The cross members are tied between upper rigid beam structure on adjacent inboard and outboard units, the structure including an upper plate, cam support and transverse and fore-and-aft stiffeners. Each outboard unit includes a diagonal brace connected to the rigid beam structure to absorb fore-and-aft loading and thereby eliminate need for a lower stabilizer. Two high volume picker drums on adjacent inboard and outboard units are serviced by a single discharge structure supported from the inboard unit and connected to a single cotton conveying duct. A hinged baffle plate extends rearwardly from the outboard unit to the discharge structure, and pivots to permit the units to be adjusted with respect to each other.

Abstract: An upper stalk guide or control for a forage harvester header. The stalk control comprises a transverse member spaced above the crop conveying passageways of the header, two outwardly and forwardly diverging arms attached to the respective ends of the transverse member and a centrally disposed wedge member for subdividing the upper portions of the crop stalks so as to enhance the clog-free feeding of the butt ends of the stalk through the crop receiving passageways of the header and into the throat of the harvester in advance of the upper portions.

Abstract: A brush windrower for accumulating brush and trimmings from under orchard trees, in which a main frame extends rearwardly from a tractor which is driven between the tree rows, and a rake bar extends outwardly from the main frame and passes underneath the overhanging branches to gather the brush. The rake bar is pivotally attached to the main frame and a hydraulic cylinder swings the rake bar around the pivot point to move the accumulated brush into the drive middles of the orchard. The rake bar is hinged to permit the rake teeth to tilt, thereby fully releasing the brush. Depth of extension of the rake bar is regulated hydraulically or by adding extensions to the rake bar. The rake bar also can be tilted to sweep evenly across sloping ground.

Abstract: Apparatus for manufacturing a yarn comprises two juxtaposed, closely spaced apart vacuum drums, which rotate in the same sense and have vacuum zones that adjoin the triangular space between the drum. A drawing frame delivers a drawn sliver at one end of said drums to said triangular space, in which the sliver is twisted to form a yarn, which is then withdrawn by means provided at the opposite end of the drums. To ensure a uniform quality of the yarn and to enable the yarn to be withdrawn at high speed, at least one additional roller drawing frame is provided, which has a delivery end disposed over the triangular space and can be operated to deliver wrapping fibers in the form of at least one stream of drawn fibers moving transversely to the longitudinal direction of the drums to the sliver, which extends in the longitudinal direction of the drums.

Abstract: A centralized control system for open end spinning machines comprises a group control unit essentially consisting of a first spinning control means composed of a plurality of sequentially operated logical elements connected in series, the first spinning control means producing from the respective logical elements parallel outputs each of which is fed to a plurality of spinning units so as to control the spinning operation thereof, and an individual control unit essentially consisting of a second spinning control means each of which constituent is the same as the first spinning control means. A spinning mechanism includes a yarn breakage sensor provided in the stream of spun yarn, a driving means for driving the spinning mechanism including a plurality of driving motors, controlled by the output from the group or individual control unit.

Abstract: A method of and apparatus for removing dirt particles from staple fibers and straightening the resulting clean fibers in an open-end spinning unit which includes means for feeding sliver, fiber opening means, and means for twisting the thus cleaned and opened fibers. Fibers together with dirt particles contained therein are accelerated by the opening action and are exposed to a first air flow which, by its deceleration due to its expansion, separates the dirt particles from the fibers. Immediately thereafter, the thus cleaned fibers are exposed to a second air flow by which they are straightened due to an acceleration imparted to them by said second air flow.In the apparatus of the invention there are provided three sectors, viz. a fiber opening sector, a dirt discharging sector, and a fiber straightening sector, in that order, the dirt discharging sector merging with the fiber straightening sector via a widened mouth.

Abstract: An accumulation of heat which takes place in gas turbines during deceleration of turbine components, such as during shut-down, may be dissipated by flowing a supply of cooling air through the turbine stages. The cooling air is selectively supplied after the supply of combustion air and fuel has been discontinued. The cooling air is preferably flowed through the combustion chambers prior to entry into the turbine stages so that the cooling air is initially pre-heated. Additional air may preferably be supplied to the final ring of blades of each stage or of the final stage of a multi-staged turbine.

Abstract: A cross-ignition assembly with a cross-fire tube supported intermediate two adjacent combustors by mounting plates affixed thereto so as to provide a conduit for the flow of hot combustion gases therebetween. The cross-fire tube comprises coaxial telescoping tubular members. A leaf spring retains the outer end of each tubular member in its operative position to effect a cantilever support for each end of the cross-fire tube. A series of cooperating air passageways and channels allow cooling air to flow across the outside and along the inside of the cross-fire tube.

Abstract: A gas turbine engine comprises an annular combustion chamber (13) intended for low nitrogen oxide emission. The chamber has a pre-mixing section (20) in which an air-fuel mixture is brought to a significant degree of vaporization before issuing through a grill (22) at the end of the pre-mixing section into a main section (21) of the chamber. Pilot sections (18,19) at opposite sides of the pre-mixing section have outlets (28,29) through which burning mixture from the pilot sections is discharged into main section (21). The grill (22) defines openings (35) through which the fresh mixture from the pre-mixing section (20) is discharged across the outlets (28,29) of the pilot sections (18,19) to mix with and become ignited by the burning mixture.The pre-mixing section (20) is an annular duct (33) having walls (15,16) which extend in the direction of the axis of the chamber and are straight in that direction though slightly convergent. The arrangement favors vaporization in the duct without auto-ignition.

Abstract: Disclosed is a split engine control system wherein the intake manifold is segmented by a shut-off valve into a first chamber portion leading to a first group of cylinders and a second chamber portion leading to a second group of cylinders. During periods of relatively low load, the cylinders of the second group are deactivated and the shut-off valve is closed to isolate the second chamber from the first chamber to cut off air supply to the deactivated cylinders. Exhaust gases are recirculated through the deactivated cylinders so that their pumping loss is minimized. A pressure detector is provided to detect a pressure difference which might develop between the first and second chambers during the partial cylinder operation to control the flow rate of the recirculated gases until the pressure difference reduces substantially to zero.

Abstract: A heat exchanger for use with two media, one of which is to be heated up and the other of which is to be cooled down. The heat exchanger has an inlet and an outlet for the medium which is to be cooled down, as well as a plurality of parallel conduits which are connected between the inlet and outlet so that the medium flows through the conduits as it passes through the heat exchanger. The conduits are connected to each other such that the medium changes its direction of flow by 180.degree. at least once between the point where it enters the heat exchanger through the inlet and the point where it leaves the heat exchanger through the outlet.

Abstract: A pump jack for pumping oil and like wells having a polish rod extending vertically out of a well casing is provided including a frame adapted to fit over said well, a hydraulic cylinder depending from said frame generally coaxially of said polish rod, a piston movable in said cylinder and having an end engaging said polish rod, a source of high pressure fluid connected to said cylinder for raising said piston in the cylinder, dump means on said frame simultaneously discharging the raising fluid from said cylinder and by-passing fluid from said source of high pressure fluid to said source of fluid, means on said piston selectively actuating said dump valve from a first position where all fluid from the source of high pressure fluid is delivered to one side of the cylinder for raising the piston to a second position where all fluid from the source and from said one side of the piston is simultaneously returned to the source and to the other side of the cylinder whereby the piston and polish rod are successivel

Abstract: An improved hot gas engine heater head where a thermocouple is coaxially positioned in an isolation tube having one closed end and the isolation tube is coaxially positioned in one of a plurality of heater tubes forming a part of a working gas path between two variable volume chambers and traversing a combustion gas flow path. The thermo-couple is in heat-transfer contact with the working gas and is physically isolated from the working and combustion gases. The temperature signal from the thermo-couple is conducted by a conduction wire passing through heat insulating material such that neither the thermo-couple nor the conduction wire is exposed directly to the working gas or the combustion gas.